Foldable treadmill

ABSTRACT

A foldable treadmill includes a base frame, a tread base having a roller assembly provided at its front side for reciprocating on the base frame, two supports each having two ends respectively pivoted to the base frame and the tread base, and a plurality of spring members connected between the base frame and the tread base for pulling the tread base to turn the tread base about the pivoted point at the supports to the received position while a rear side of the tread base is lifted from the floor by an external force.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to treadmills and more particularly, to a foldable treadmill.

2. Description of the Related Art

A regular treadmill is generally comprised of a base frame and a tread base. The base frame is placed on the floor, having a front handrail upwardly extended from a front side thereof. The tread base is mounted on the base frame. While walking on a treading belt of the tread base, the user can hold the front handrail with the hands. In order to save storage space, a treadmill may be made foldable. A known foldable treadmill comprises an actuator, for example, a pneumatic or hydraulic system. The actuator has a fixed end pivoted to the base frame, and an output end connected to a rear bottom side of the tread base. The user can use a controller to extend the output end out of the fixed end of the actuator and to further lift the rear side of the tread base, thereby turning the tread base to a folded non-operative status.

The aforesaid foldable treadmill is functional, however the actuator greatly increases the manufacturing cost of the treadmill. Further, it is inconvenient to control the operation of the actuator through the controller.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a foldable treadmill, which production cost is preferably low and which is convenient for operation.

To achieve the foregoing objects of the present invention, the foldable treadmill comprises a base frame placed on the floor having a front side and a rear side, a tread base mounted on the base frame and having a roller assembly disposed at its front side for reciprocating on the base frame, at least one support each having two ends respectively pivoted to the base frame and the tread base, and at least one spring member each having two ends respectively connected to the tread base and the rear side of the base frame. When the roller assembly is moved to the front side of the base frame, each spring member is stretched, and the tread base and the support are received in the base frame. When the rear side of the tread base is lifted from the floor, each spring member pulls the roller assembly toward the rear side of the base frame, and the tread base pivots relatively to the support to move the rear side thereof upwards.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a preferred embodiment of the present invention.

FIG. 2 is a front view of the preferred embodiment of the present invention, showing that a tread base is in a horizontal position.

FIG. 3 is similar to FIG. 2, showing that the tread base is tilted relatively to a base frame.

FIG. 4 is a front view of the preferred embodiment of the present invention, showing that the tread base is in a folded status.

FIG. 5 is similar to FIG. 4, showing that a sliding bar is unlocked from a locking member.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 1 and 2, a foldable treadmill in accordance with a preferred embodiment of the present invention is shown comprised of a base frame 10, a tread base 20, two supports 40, and four spring members 50.

The base frame 10 is a rectangular frame formed of metal tubes by welding for being steadily placed on the floor, including a left-side tube 11, a right-side tube 12, two guide tubes 13, a front tube 14, a rear tube 15, a locating rod 19 axially mounted in the rear tube 15, a front handrail 17 mounted on the front tube 14 for holding by the user, and bottom plate 29 mounted at a bottom side thereof. The left-side tube 11 and the right-side tube 12 are vertically connected between the front tube 14 and the rear tube 15 end by end. The guide tubes 13 are arranged in parallel to the left-side tube 11 and the right-side tube 12. The left-side tube 11, the right-side tube 12, and the guide tubes 13 each have a sliding slot 16 extended along a long axle thereof. The guide tubes 13 each include a locating axle 18 at a rear side thereof relatively to the respective sliding slot 16.

The tread base 20 is mounted on the base frame 10, including a front frame 21, a rear frame 22, a left-side frame 23, a right-side frame 24, a treading belt assembly 25 provided between the left-side frame 23 and the right-side frame 24 for the user's running thereon, a first (tread base) motor 26 for driving the treading belt assembly 25, a foot member 27 provided at a bottom side of the rear frame 22 for standing on the floor, and a second (tilting) motor 31 mounted in the tread base 20. The second motor 31 has an output shaft 32 facing downwards and having a push member 34 threadedly disposed on an outer periphery thereof. According to the present preferred embodiment, the output shaft 32 is a screw rod, and the push member 34 is a female screw threaded onto the output shaft 32. The female screw 34 has an end threaded onto the output shaft 32 of the second motor 31, and the other end pivoted to a transversely extended pivot rod 35. Two tilting rods 36 are respectively provided at two distal ends of the pivot rod 35. The tilting rods 36 each have a rear end pivoted to a respective locating axle 28 at one side (left-side frame 23 or right-side frame 24) of the tread base 20, and a front end extending toward the front frame 21 of the tread base 20. The front frame 21 of the tread base 20 is provided with a roller assembly 37. The roller assembly 37 includes a transversely extended sliding bar 38, and two rollers 39 pivoted to two distal ends of the sliding bar 38. The sliding bar 38 is pivotally coupled between the front ends of the tilting rods 36, and movable along the sliding slots 16 of the left-side tube 11, right-side tube 12 and the guide tubes 13 of the base frame 10. The rollers 39 are supported on the bottom plate 29, and movable together with the sliding bar 38 along the guide tubes 13.

The two supports 40 are narrow flat bars arranged between the guide tubes 13 and the tilting rods 36, each having two ends respectively pivoted to the locating axles 18 of the base frame 10 and to the transversely extended pivot rod 35.

The spring members 50 are spiral tensile springs respectively mounted in the left-side tube 11, right-side tube 12 and guide tubes 13 of the base frame 10, each having an end connected to the locating rod 19 of the base frame 10 and the other end connected to the sliding bar 38. When the spring members 50 are in the fully extended status, the sliding bar 38 is stopped at a front side of each sliding slot 16, and a folding torque generated from the resilience of the spring members 50 can pull the sliding bar 38 to a rear side of each sliding slot 16 by a proper external force.

Further, a locking member 60 is pivoted to the locating axle 18 for being pivotable between a locking position and an unlocking position. A spring member 63 is provided to hold the locking member 60 in the locking position. The locking member 60 has an end terminating in a hooked locking portion 62 and the other end terminating in a footplate portion 61. When the sliding bar 38 is moved to the rear side of each sliding slot 16, the hooked locking portion 62 of the locking member 60 is hooked on the sliding bar 38 to lock the sliding bar 38 (see FIG. 4). When the user presses the footplate portion 61 with the foot, the locking member 60 pivots to be disengaged from the sliding bar 38 (see FIG. 5).

As illustrated in FIG. 3, when the output shaft 32 of the second motor 31 is rotated in a predetermined direction, the female screw 34 is spirally rotated forwards to turn the pivot rod 35, thereby causing the front frame 21 of the tread base 20 to be lifted from the base frame 10, and therefore the tread base 20 is returned to the position in parallel to the floor.

When intending to fold the tread base 20, the user must lift the rear frame 22 of the tread base 20 with an external force (for example, by hand) to generate a folding torque to lift the foot member 27 from the floor. As shown in FIG. 4, while the foot member 27 is away from the floor for a distance, the folding torque of the spring members 50 is acted on the sliding bar 38 of the roller assembly 37, thereby causing the rollers 39 to move backwards on the bottom plate 29 toward a rear side of the bottom plate 29 and pulling the sliding bar 38 to the rear side of the sliding slot 16. When the sliding bar 38 is moved to the rear side of each sliding slot 16, the tilting rods 36 pivot relatively to the respective supports 40, thereby causing the female screw 34 and the output shaft 32 to turn the tread base 20 to a folded position and to further move the supports 40 to stand upright. Further, when the sliding bar 38 is moved to the rear side of the sliding slot 16, the hooked locking portion 62 of the locking member 60 is hooked on the sliding bar 38 to lock the sliding bar 38. As illustrated in FIG. 5, when the user presses the footplate portion 61 with the foot, the locking member 60 is turned to be disengaged from the sliding bar 38, for enabling the tread base 20 to be returned to an operative status.

From the above recitation, the treadmill of the present invention achieves the desired folding function with a relatively low production cost and relatively more convenient operation procedure.

In order to prevent accidental reversion of the tread base in the folded status, a fixer can be additionally installed at the handrail to fix the tread base in the received position, and a locker can be additionally installed between the base frame and the tread base to lock the tread base in the operative position. 

1. A foldable treadmill comprising: a base frame placed on the floor; a tread base mounted on said base frame and having a roller assembly mounted at its front side for reciprocating along said base frame; at least one support each having two ends respectively pivotally connected with said base frame and said tread base; and at least one spring member each having two ends respectively connected with said tread base and a rear side of said base frame; whereby while said roller assembly is moved to a front side of said base frame to stretch said spring member, said tread base and said support are received in said base frame; while a rear side of said tread base is lifted from the floor by an external force, each said spring member pulls said roller assembly to move toward the rear side of said base frame, and said tread base is turned relatively to said support to move the rear side thereof to be turnup to enable said treadmill in a folded status.
 2. The foldable treadmill as defined in claim 1, wherein said base frame comprises a left-side tube, a right-side tube, at least one guide tube, a front tube, and a rear tube, a front tube, said left-side and right-side tubes and said guide tube being parallel to one another, said left-side and right-side tubes each being vertically connected between ends of said front and rear tubes, said guide tubes each being mounted between said left-side and right-side tubes, said at least one spring member each being mounted in said left-side and right-side tubes and each said guide tube.
 3. The foldable treadmill as defined in claim 2, wherein said tread base comprises a tilting motor having an output shaft facing downwards for moving a push member, said push rod having a pivot rod pivotally connected to its distal end, said pivot rod having two tilting rods respectively provided at its two distal ends, said tilting rods each having an end pivotally connected with said base frame and the other end extending toward the front side of said tread base; said roller assembly is pivotally mounted to front ends of said two tilting rods.
 4. The foldable treadmill as defined in claim 3, wherein said roller assembly comprises a sliding bar and at least one roller, said sliding bar being pivotally coupled to the front end of each said tilting rod, said at least one roller each being provided for reciprocating on said base frame.
 5. The foldable treadmill as defined in claim 4, wherein said base frame comprises a locating rod axially mounted in said rear tube of said base frame; said at least one spring member each has two ends respectively connected to said sliding bar and said locating rod for generating resilience for pulling said sliding bar from the front end to the rear end of said base frame.
 6. The foldable treadmill as defined in claim 5, wherein said left-side tube, said right-side tube, and said at least one guide tube each have a sliding slot; said at least one guide tube each has a locating axle at a rear side of each said locating axle; said at least one support each has an end pivotally connected to said locating axel; said sliding bar is inserted through said sliding slots of said left-side tube, said right-side tube, and said at least one guide tube.
 7. The foldable treadmill as defined in claim 6, wherein said at least one support each has two ends respectively pivotally connected to said locating axles and said pivot rod of said tread base.
 8. The foldable treadmill as defined in claim 1, wherein said base frame comprises a handrail upwardly extended from a front side thereof, and a fixer mounted on said handrail for fixing said tread base to said handrail while a rear end said tread base is turnup in the folded status.
 9. The foldable treadmill as defined in claim 8, wherein said tread base comprises a locker for locking said tread base to said base frame to prevent returning to the folded status.
 10. The foldable treadmill as defined in claim 1, wherein said base frame further comprises a locking member pivotally mounted thereon for locking said tread base while said tread base is in a folded status, said locking member having a locking portion and a footplate portion, whereby when the tread base is turned to the folded status by the resilience of said at least one spring member, said locking portion locks said tread base to said base frame; when the user treads on said footplate portion, said locking portion is partially detached from said tread base. 